/Engine/Plugins/Importers/USDImporter/Source/UnrealUSDWrapper/Public/UnrealUSDWrapper.h
Returns all the stages that are currently opened in the USD utils stage cache, shared between C++ and Python
static [TArray](API\Runtime\Core\Containers\TArray)< [UE::FUsdStage](API\Plugins\UnrealUSDWrapper\UsdWrappers\FUsdStage) > GetAllStagesFromCache()